Shared computing resources are well known in the art. Since the 1960s, time-sharing resources have been in place, in which individuals or enterprises could pay for batch processing, such as by submitting batches on punch cards or paper tape, and waiting to later receive an output. Over time, such systems evolved in both structure and purpose. In more modern practice, managed hosting may enable a person or enterprise to purchase computing resource by, for example, the processor-hour. These are often used for tasks such as serving web traffic, and may be hosted on computers residing in a large data center. In something of a reversal of the same phenomenon, some individual users may “donate” spare processing capacity to favorite projects. For example, “SETI@home” volunteer processing capacity to analyze radio signals for evidence of extra-terrestrial intelligence.